This invention relates to walkers and wheelchairs in general, and more particularly, to an apparatus that is capable of being converted from a walker to a wheelchair.
Supports for the handicapped and physically disabled are usually provided with varying levels of functionality. The conventional walker, for example, provides a user a with a stationary support and a means for maneuvering along a planar surface. If a walker is provided with wheels at one or both ends, then the level of mobility, along with the functionality of the apparatus, increases.
A further increase in functionality can be seen with the presence ancillary features that benefit the user during times of rest. For example, the walkers of U.S. Pat. Nos. 1,448,783 to Blewitt et al. and 3,354,893 to Schmerl are provided with a seat that pivots from a horizontal, use position within the center of the walker framework, to a vertical, non-use position, which is alongside the front of the walker and out of the way of the standing and moving operator. The seat not only contributes a highly desirable functional feature, but also adds a level of comfort and confidence in the operator should the operator need to rest suddenly or otherwise.
As the art evolved, other combination apparatus appeared wherein the conventional walker was combined with the comfort features of a wheelchair. As used herein, the term xe2x80x9cwheelchairxe2x80x9d is defined as a patient or user transport device, and not of the self-propelled variety. For example, U.S. Pat. Nos. 5,419,571 to Vaughan and 5,451,193 to Pickard both illustrate a four-wheeled wheelchair having an upwardly pivoting seat and arm rests that function as walker supports. When the seated operator of the wheelchair desires to walk, he or she merely lifts the seat and maneuvers the chair around using the wheelchair arm rests as handlebars. In both cases, the operator walks in the space where the seat used to exist.
Alternative designs for combination wheelchair/walkers exist. For example, in U.S. Pat. No. 5,558,358 to Johnson, a wheelchair seat is pivoted out of the way and the sides of the wheelchair are then partially collapsed to form a triangular wheel base configuration, with the operator using the wheelchair handlebars as a walker support. As another example, in U.S. Pat. No. 5,741,020 to Harroun, a walker support is provided as a forward extension of a wheelchair frame, allowing the seated individual to access the walker support by merely standing from the seat without re-orienting with respect to the seat.
The prior art is thus replete with combination apparatus that allow an operator to use the same device as both a walker and transport wheelchair, with varying levels of comfort and functionality. In all instances, however, the ground-engaging aspects of the apparatus, such as the wheels of a chair or the rubber feet of a conventional walker, remain unchanged during the conversion from walker to wheelchair and vice versa. In certain situations it would be desirable to have four wheels engaging the ground when being moved in a wheelchair, but only two wheels engaging the ground when operating a device as a walker. For example, if the operator used a combination device primarily as a support where it was necessary to be effectively xe2x80x9cplantedxe2x80x9d in a particular location in between spurts of motion, the presence of four ground-engaging wheels might provide an unsatisfactory level of instability during resting conditions. In such a situation, for example, it would be desirable if at least one set of wheels could be converted into non-rotational feet that would effectively grip the ground during positions of rest, with the other set of wheels being used during periods of mobility.
The present inventor is not aware of any combination devices having convertible ground-engaging members featuring this level of functionality. There is a need, therefore, for a device that is convertible between a walker and wheelchair having convertible ground engaging members that provide varying levels of support and mobility. The apparatus of the present invention fulfills such need.
It is an object of the present invention, therefore, to provide a device that is convertible between a walker and wheelchair and provides varying levels of support and mobility for the operator.
It is another object of the present invention to provide a device that is convertible between a walker and a wheelchair and vice versa that is easy to use, operate, transport and store.
It is still another object of the present invention to provide a device that is convertible between a walker having two wheels and a wheelchair having four wheels.
It is still another object of the present invention to provide a convertible walker/wheelchair having two pairs of wheels, one pair being in continuous engagement with the ground and the other pair being in selective engagement with the ground.
Still other objects and advantages of the invention will become clear upon review of the following detailed description in conjunction with the appended drawings.
An apparatus that is convertible between walker and a chair has one pair of wheels that are continually engaged with the ground, floor or the like, and a second pair of wheels that are movable from a first position out of engagement or disengaged with the ground, in which the apparatus is used as a walker, to a second position into engagement with the ground, in which the apparatus is used as a non-self-propelled wheelchair. The movable wheels are controllable by the operator through the use of handle members connected such wheels. The handle members rotate the wheels into and out of engagement with the ground along a path that is at an angle from the vertical, thereby assuring disengagement of the wheels from the ground.